Along with the social development and continuous progress of science and technology, the electric tool, the unmanned machine, the mobile phone and other electronic products in use of battery are increasingly applied for being not limited by power source. However, the battery for the electric tool, the unmanned machine and others can be charged by special charger; the electric tool cannot be used after the power failure if no special charger is carried along; it is also inconvenient to use the electric tool under the poor light condition, the safety hidden trouble may be caused since other person may not find out the user. Besides, some electronic products cannot be used at the place without external power source when the products are out of power source. The application of some existing chargers is single and needs to improve.